Investigations are proposed to characterize 1) the functional relationship between the activation status of peripheral blood and bronchoalveolar lavage fluid eosinophils and the degree of airway narrowing produced by local allergen challenge, 2) interaction between eosinophils adhesion to intercellular and extracellular matrix protein and the activated metabolic substances of these cells, and 3) the cell-cell interaction among eosinophls-epithelial-smooth muscle cells in the challenged area in vivo and in vitro.